Originally Posted by GunsOfNavarone
Where are you buying the transmission pans with drain plugs? I have seen aftermarket differential covers with drain plugs, but not transmission pans.
I drilled and tapped the regular transmission pan for the 4L80E. Then used a 3/8" Grade 8 fine thread with a lock washer, 3 washers, and a rubber washer.
I almost drilled a hole then welded a nut on to the pan.
I'm not sure which vehicle you're looking for, but I think for almost any RWD GM transmission they probably make one.